Nothing could be done in the body without water. It dissolves the food, carries the blood corpuscles, moistens the lining membranes of the mouth, nose, throat, and all the inside of the body, forms a sort of water cushion around the heart, lungs, and organs of the abdomen, cools us by evaporation as sweat, and does many other useful things. And the more water in the body the more vigorous the life. Restless children have more than adults, and the sluggishness of old age is in great measure due to a sort of bodily drought.
Ordinary table salt, a mixture of solid sodium and gaseous chlorine, does a lot of work in the human body. It seems necessary to the life of every organ, and is found in the blood, muscles, and all the other fluids and solids. It helps the fluids to pass through the thin membranes, so that as well as promoting the absorption of food from intestines and stomach into the blood current it also promotes the percolation of the blood from the minute arteries out into the tissues.
Experiments show that if salt be withheld from an animal he quickly languishes and dies. Yet there are only between six and seven ounces in the whole human fabric, but quite enough to provide a large size dinner table with it. Singularly the body is rather extravagant with its small supply of this important constituent, and loses half an ounce every day.
SALT SUFFICIENT TO FILL THIS CELLAR SIX OR SEVEN TIMES GOES TO THE MAKING OF A MAN.
Washing soda, or sodium in union with carbon and oxygen, is another substance which performs an indispensable duty. Dissolved in the blood it travels to every part of the body on a mission analogous to that of the useful dustman. Wherever it finds a particle of carbonic acid it seizes it, carries it to the lungs, and discharges it into the air. The quantity of washing soda in the blood is really very small, but the work it does is immense.
You cannot perform any action without making a given quantity of poisonous carbonic acid. Every beat of the heart and rise of the chest, even bending the finger or closing the eyes, gives rise to some of this waste product. And, if it were not continuously removed, it would fatally clog the machine in a very few minutes. The washing soda performs the necessary scavenging duty.
This washing soda is also an important part of bone; mingled with phosphate of lime, phosphate of magnesia, and fluoride of lime, it helps to make our bones and teeth.
Smelling salts seems a funny thing to have within you, but it is there. Sodium, potassium, and ammonium are mixed with hydrogen and oxygen to make it—the pungent ammonia, as well as the soda and potash which are the cleansing principles of soap. These are distributed through all the flesh of the body and are present in the blood. Together with the phosphates they keep the blood and other fluids alkaline. This means that they preserve us from another of the many conditions fatal to life, for if the blood turned acid we should die.
Chloride of ammonium, the familiar inhalement, is another of what might be called the body's spices; so is chloride of potash, a sort of cousin of the popular sore throat cure; and so also is hydrochloric acid.